<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        input[type="file"]{
            display: none;
        }
    </style>
</head>
<body>
    <button id="upload-button">点击上传</button>
    <input type="file" title="上传小于5m的文件" id="upload-input">
    <script>
        let uploadButton=document.getElementById('upload-button');
        let uploadInput=document.getElementById('upload-input');
        uploadButton.onclick=function(){
            uploadInput.click();
        }
    </script>
</body>
</html>